

package com.hazelcast.jet.impl.pipeline.transform;

import com.hazelcast.function.FunctionEx;
import com.hazelcast.function.ToLongFunctionEx;
import com.hazelcast.jet.Traverser;
import com.hazelcast.jet.function.TriFunction;
import com.hazelcast.jet.impl.pipeline.PipelineImpl.Context;
import com.hazelcast.jet.impl.pipeline.Planner;
import com.hazelcast.jet.impl.pipeline.Planner.PlannerVertex;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.io.Serial;
import java.util.function.Supplier;

import static com.hazelcast.jet.core.Vertex.LOCAL_PARALLELISM_USE_DEFAULT;
import static com.hazelcast.jet.core.processor.Processors.flatMapStatefulP;

public class FlatMapStatefulTransform<T, K, S, R> extends StatefulKeyedTransformBase<T, K, S> {

    @Serial
    private static final long serialVersionUID = 1L;

    private final TriFunction<? super S, ? super K, ? super T, ? extends Traverser<R>> statefulFlatMapFn;
    private final TriFunction<? super S, ? super K, ? super Long, ? extends Traverser<R>> onEvictFn;

    public FlatMapStatefulTransform(@Nonnull Transform upstream, long ttl, @Nonnull FunctionEx<? super T, ? extends K> keyFn, @Nonnull ToLongFunctionEx<? super T> timestampFn, @Nonnull Supplier<? extends S> createFn, @Nonnull TriFunction<? super S, ? super K, ? super T, ? extends Traverser<R>> flatMapFn, @Nullable TriFunction<? super S, ? super K, ? super Long, ? extends Traverser<R>> onEvictFn) {
        super("flatmap-stateful-keyed", upstream, ttl, keyFn, timestampFn, createFn);
        this.statefulFlatMapFn = flatMapFn;
        this.onEvictFn = onEvictFn;
    }

    @Override
    public void addToDag(Planner p, Context context) {
        determineLocalParallelism(LOCAL_PARALLELISM_USE_DEFAULT, context, false);
        PlannerVertex pv = p.addVertex(this, name(), determinedLocalParallelism(), flatMapStatefulP(ttl, keyFn, timestampFn, createFn, statefulFlatMapFn, onEvictFn));
        p.addEdges(this, pv.v, edge -> edge.partitioned(keyFn).distributed());
    }
}
